It highlights setco-op and says invalid argument. formX is the one and only form there, but I can't use Me.hWnd because I'm in a module. This is how the tutorial does it- and that seems to run. Thanks for any help, I'm using VB5 and DX 7 (of course).

And I thought it might be something to do with the fullscreen thing, but I tried modifying the tutorial and taking out that parameter and it still runs without error, although no output is created. But I just tried your suggestion and it worked. WTH? Why doesn't it mess up the tutorial? Oh well.